DCIS yet lymph nodes affected?

Hello all - I am confused about this, perhaps someone out there can explain it to me. I had DCIS, and I understood that this is a non-invasive condition, meaning that the abnormal cells are confined within the milk ducts and so have not spread outside them. I did have SNB at the same time as my m-op, 4 nodes were taken, and found to be clear. I thought the reason for testing the nodes is because they can’t know before the operation whether it is in fact all DCIS or whether there may in fact be an actual invasive cancer in there, as they diagnose DCIS from a biopsy which can’t tell them everything. So they check the nodes just in case there might have been an invasive cancer, which could then have spread.

However, if there was no invasive cancer, how could it have spread? I am puzzled that women are finding after their ops that their lymph nodes are affected and yet their initial diagnosis of DCIS remains. How can that be?

My understanding (though I am no expert!) is that at some stage DCIS can become invasive i.e. sending invasive cells off into the system, and no-one knows quite when … or if it has happened already.

Maybe someone knows a more definite explanation??


My IDC was surrounded by small area of DCIS which was only found at op.They just need to be sure I think…

Horace, same with me IDC surrounded by small area of DCIS and my bcn said that this is quite common.

Eliza xx

Hey ladies, I was a bit confused yesterday when I got my results too!
The IDC was all cleared…but then they found DCIS in the margins, and now ‘need’ another op WLE again next week! They first suggested a MX, then backtracked to the ‘lesser’ option. I just wondered if the DCIS was there at the same time as the IDC…any ideas??
Helen x

I was told that DCIS doesn’t need the lymph nodes removing, though if the biopsy (during the op) shows that it’s progressed(i.e the changes mean that it has become invasive) then the nodes will then need removing. At diagnosis I was told that they would be removed but a few weeks later the surgoen said no. It seems that this is something that they are debating I think and even within the one hospital there were various views!

I had extensive DCIS (mastectomy done last month) and the SNB revealed invasion in a lymph node but I have been told no further treatment needed. (I started thread on this in the DCIS/LCIS subject area.) I’m as confused as anyone!